## Sarah_Miller720 Group Title What is the slope of the line? one year ago one year ago

1. Sarah_Miller720

I got -2

2. JayDS

noo...

3. Sarah_Miller720

why?

4. JayDS

it will be undefined.

5. JayDS

or zero, let me check.

6. tkhunny

You are going to have to demonstrate how you managed that. Since ALL y-values are the same, your numerator should be zero.

7. Sarah_Miller720

never mind if cant be -2 because to find the slope you have to do the rise and run thing and in this problem there isn't a rise

8. JayDS

**The gradient of a horizontal straight line will be zero. Let me explain.

9. Sarah_Miller720

it*

10. JayDS

u are right.

11. tkhunny

No, there IS a rise, and it is zero! That is quite a bit different from "there is no rise".

12. JayDS

lets choose two points. (0,-2) (1,-2) and use the gradient formula to figure out the gradient. y=(-2--2)/(1-0) y=0/1 y=0

13. zordoloom

No slope exists for horizontal lines. This line would be called y=-2

14. tkhunny

Let's get it straight, folks: Horizontal Line: Zero Slope (Calculated Numerator is Zero) Vertical Line: No Slope (Calculated Denominator is Zero)

15. zordoloom

Don't by mistake write y=-2x, because that would mean that the slope is -2. Instead the line is just simply y=-2. And to correct @tkhunny, a horizontal line has no slope, and a vertical line has an undefined slope.

16. tkhunny

Seriously? Please read a better author. Horizontal Line: The slope is zero. m = 0. It is, therefore "Zero Slope". Vertical Line: The slope is not defined. m failes to exist. It is, therefore "No Slope".

17. tkhunny

The phrase "has an undefined slope" is not well-defined. If the slope is "undefined", nothing "has" it. It doesn't exist. The more precise language, for a vertical line, would be. "The slope is indefined." and "The line has no slope."